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Why Is My Puffer Fish Floating?

Pufferfish are delicate organisms that display symptoms of illness when they become ill.

They sink to the bottom and swim in circles or puff out to show they’re sick. It is critical to recognize the indicators of sickness and treat them as soon as possible. So, Why Is My Puffer Fish Floating?

Animals display symptoms to alert us to the fact that something is wrong with them. It is vital to be aware of the pufferfish’s unusual behaviors.

Knowing about a pet’s common and unusual behavior as a pet parent will help us maintain the pet healthy.

The purpose of this article is to educate readers on the reasons behind pufferfish floating.

The article will also go over the illnesses and circumstances that cause a pufferfish to float. So, to find out what to do if a pufferfish is floating, read the article to the end.

Why Is My Puffer Fish Floating?

Pufferfish have an unusual behavior of floating. When they are unwell, puffy, or dead, they float. Changes in water parameters can cause stress, which might result in floating.

Pufferfish puff up and start floating when there is a lack of oxygen in the water.

Pufferfish that are floating require a quick assistance. When the swim bladder of a pufferfish is compromised, it causes them to float. Furthermore, when a pufferfish dies, its body floats to the surface of the water.

Swim Bladder Disorder

Pufferfish are blown up or have swim bladder disorder
Pufferfish are blown up or have swim bladder disorder

The swim bladder is a gas-filled organ located in the lower part of the pufferfish’s body that aids with buoyancy.

The pufferfish begins to float on the surface of the water when its swim bladder becomes overly full owing to any ailment.

The swim bladder condition can be caused by the compression of other organs, which causes the bladder to malfunction.

Bladder difficulties can also be caused by infection or physical harm. Swim bladder issues, on the other hand, are easy to treat.

Puff Up

When pufferfish puff up, they float at the surface of the water. Puffing up is a protective strategy used by pufferfish to avoid being eaten by predators.

Because the spine covers the pufferfish’s body as it puffs out, biting the pufferfish is tough.

When you put a new pufferfish in the tank after it has been transported, it floats to the top of the water. Because of the stress caused by transportation, pufferfish puff up.

A pufferfish that has been puffed up has a larger surface area and may float more freely in the water.


Pufferfish that have died float near the surface of the water, still and unresponsive. You may notice dead pufferfish floating upside down on the seashore.

They drink too much water, causing their stomachs to expand and their muscles to stretch.

Not moving, irresponsive to stimuli, and floating upside down are all indicators of a dead floating pufferfish. The deceased pufferfish must be removed from the aquarium.

Even if the pufferfish is dead, do not handle it immediately. Because it has spines that are potentially hazardous to humans.

Dead pufferfish floating upside down on the seashore
Dead pufferfish floating upside down on the seashore

What Should You Do If Puffer Fish Floating?

The most crucial element is to understand why a pufferfish is floating. If the pufferfish is dead, it must be removed from the aquarium.

Because the inflated pufferfish’s body is covered in spikes, carefully handle it and remove it from the tank.

If the pufferfish has inflated, it is critical to eliminate the cause of the inflated pufferfish. Stress and a lack of oxygen in the aquarium cause pufferfish to puff up. You must maintain good water parameters and eliminate pufferfish hazards.

If your pufferfish is sick and has a swim bladder problem, you should get medical help from a veterinarian.

The swim bladder’s function may be harmed by the compression of organs around it. As a result, the pufferfish’s swim bladder fills up with gas and floats.

Because of the swim bladder infection, the pufferfish may appear dull and lethargic. As a result, it floats on the water’s surface without moving.

As a result, determining the reason for floating and treating the illness appropriately is critical.


How to tell if your puffer fish is dying? 

By observing the signs and symptoms, you can determine whether or not your pufferfish is dying.

Lethargic, loss of appetite, loss of pigmentation, fin rot, and floating are all signs of a dying pufferfish.

If you detect these symptoms, your pufferfish is suffering from a serious illness and is on the verge of dying.

Why is my puffer fish curled up?

Stress and illness are indicated by the curled-up pufferfish. Poor water quality and excessive amounts of ammonia, nitrates, and nitrites in the tank can induce stress.

Pufferfish like to dwell in small groups or alone. On the other side, a huge number of little fish in a tank might cause stress.

Why is my puffer swimming in circles?

Pufferfish become nervous when there are high nitrate levels in the tank, and they begin to swim in circles.

Aside from that, you should look around the tank for anything alarming. because the pufferfish is attempting to flee from something. 

How can you tell if a puffer fish is stressed?

A stressed pufferfish swims up and down a lot. Due to the stress, the pufferfish may curl up.

The pufferfish’s puffy appearance indicates that it is stressed. As a result, it is critical to recognize such indicators and eliminate stressors.

Why is my puffer fish laying on the bottom?

After swimming too much, pufferfish lay on the bottom. It is usual if the water quality is good and there is a sufficient amount of food.

A pufferfish, on the other hand, will lay on the bottom due to low water and food quality. Sometime, pufferfish lay on the bottom when they rest.

Finals Sentences

When pufferfish are blown up or have swim bladder disorder, they float. They increase the surface area of their stomach touching the water’s surface by filling it with water.

As a result, when they reach the water’s surface, they float without moving due to their vast surface area.

Floating is an unusual habit in pufferfish, so if you see your pufferfish floating at the surface of the water.

You must figure out what is causing your pufferfish to float. Remove it from the tank if it is dead. Consult a veterinarian if it has any other issues that need to be addressed.

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